The Amazing Hubble

From the New York Times:

The space agency's finest scientific instrument escaped a death sentence on Tuesday when Michael Griffin, the NASA administrator, approved a shuttle mission to service and upgrade the Hubble Space Telescope.

It was a brave call, since repairing the Hubble will put the shuttle at greater risk than a typical mission to the International Space Station. It was also a welcome sign that NASA is willing to go the extra orbital mile to support superb science, even while it squanders large sums on completing the space station to perform research that can't begin to compare with the Hubble's in importance.

For a decade and a half, the Hubble has made discoveries that have helped revolutionize our understanding of the universe. Its typical role is to pick up a hint from ground- based telescopes and then use its unparalleled vantage point above the atmosphere to probe deeply into some puzzling phenomenon.

The Hubble has peered farther into space and farther back in time than any other instrument. It has discovered more than 500 proto-galaxies that emitted light when the universe was in its formative stages, confirmed the jaw-dropping discovery that the expansion of the universe is accelerating, and helped establish the rate of expansion and the age of the universe.

A panel of distinguished astronomers judged that the Hubble "has arguably had a greater impact on astronomy than any instrument since the original astronomical telescope of Galileo."

What made all of this possible was NASA's willingness to refurbish the Hubble every few years to replace depleted batteries and gyroscopes and install new equipment. Many experts believe that when the Hubble gets two state-of-the-art instruments on the next servicing mission in 2008 it will be more capable than ever, ready to peer farther back into a time when galaxies were forming and the universe was emerging from darkness into light.

The threat to the Hubble's future came unexpectedly from NASA itself in early 2004. In a decision that can only be described as myopic, Sean O'Keefe, the administrator at the time, unexpectedly canceled the next servicing mission, ostensibly because of safety concerns after the Columbia disaster.

But the underlying reason was almost certainly that a Hubble mission would be a diversion from the administration's priorities to complete the space station and then send astronauts back to the moon and eventually Mars. Only intervention by the U.S. Congress and the National Academy of Sciences kept the death sentence at bay.

Now Griffin has concluded that the mission can be conducted safely, especially since NASA has developed new inspection and orbital repair techniques, and that the mission will not interfere with other space priorities. A Hubble mission may be marginally more risky than a flight to the space station, but that risk is surely worth taking for the scientific payoff.